What is the vapor pressure at 20°C of an ideal solution prepared by the addition of 1.36 g of the nonvolatile solute urea,CO(NH₂)₂,to 24.1 g of methanol,CH₃OH? The vapor pressure of pure methanol at 20°C is 89.0 mmHg. A)2.6708 mmHg B)80.4 mmHg C)84.2 mmHg D)86.3 mmHg E)8.51 mmHg

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The vapor pressure of the solution is calculated using Raoult's Law. First, calculate the mole fraction of methanol. The moles of methanol are 24.1 g / 32.04 g/mol = 0.752 mol. The moles of urea are 1.36 g / 60.06 g/mol = 0.0226 mol. The mole fraction of methanol is 0.752 / (0.752 + 0.0226) = 0.9709. The vapor pressure of the solution is 0.9709 * 89.0 mmHg = 86.3 mmHg.

What Is the Vapor Pressure at 20°C of an Ideal